Apparatus for dispensing materials into the Fallopian tubes of a female through non-surgical procedures have been described in a plurality of patents issued to the inventors of this invention, including U.S. Pat. No. 3,875,939, entitled "Single Stroke Dispensing Method", issued Apr. 8, 1975, which is herein incorporated by reference in its entirety.
Through the use of such dispensing apparatus, liquid tissue adhesives are injected into the Fallopian tubes to occlude the canals of the tubes. The materials used for this purpose are generally sensitive to moisture. Therefore, these materials will quickly set up in the uterine cavity, if not quickly forced into the canals of the Fallopian tubes. This motion of the materials is done by the rapid expansion of a member which fills the uterine cavity, thus applying pressure to the materials to force them into the Fallopian tubes. It has been found that high pressures cannot be used to rapidly inject the tissue adhesive into the canals as the material may then be forced through the Fallopian canals into the body cavity, or through the walls of the uterus into the blood stream, or that the walls of the uterine cavity may, in fact, be ruptured. It is thus necessary to provide for a control of maximum pressure and an improved means for accomplishing this control is described herein. Further, once the maximum pressure is reached, it is advantageous to maintain that pressure should it be subject to change, for example due to expansion of the walls of the uterus or to the flow of the materials leaving the uterine cavity. The improved apparatus of this invention not only provides control to avoid exceeding the maximum pressure, but provides a pressure regulation to maintain the pressure substantially constant throughout the dispensing operation. A further improvement of this invention prevents retro-flow of the materials when they are placed under pressure. A still further improvement provides for a replaceable probe portion to be used with the same control portion of this invention.